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Topic: Starting a new build (Read 2547 times)

I have considered putting the wastegate on the manifold, or even directly on the exhaust housing. I would just need to find a fabricator to be able to weld onto cast iron. I have one lined up to weld my adapter together, but he's in Washington and I'm in Utah so I was going to ship drawings and the pieces to him. I think for this first iteration, I am going to try it without a wastegate. I have also been talking with some vendors who build custom adapted HX35 and HX40 turbos for 6.5L engines, and they say a stock engine will handle 15-17 psi of boost if the drive pressure stays down. They seem to think anything is better than the stock GM-8 turbo so the HE351VE should be fine. I will just need to start ultra conservative with the vein positions and go from there.

It has electronic fuel control so I’m sure that is completely adjustable in the PCM. Unfortunately there isn’t a plug in tuner for it, so I have to do it the old fashioned way and send the PCM out to be programmed.

Ok you’ve talked me out of it. I think I’m going to be around the 250 HP by the time it’s done.

Now to the controller side. I want to integrate boost, fuel pressure, and EGT sensors into the Arduino and output data to 20x4 screen. Will the Uno handle the added inputs, or should I go up to the Mega? Rx7man, I saw your post about the affordable pressure sensors, and I’m going to grab a couple of 2 bar sensors. I already have a hole tapped in the intake for a boost gauge so it will be a direct swap, and tapping into the top of the fuel filter housing is easy. I’ll track down the thermocouple amplifier board and an EGT probe too.

you should run a length of line and a snubber on the fuel side to reduce the vibration.. they really don't like it and it's a pain to filter the signal as well, and get a few spare sensors too... they do fail once in a while, I had one on the fuel side spring a leak. cheap chinese garbage, but I had a $100 Honeywell fail on me too

For a thermocouple amp board, DO NOT GET the $2 Max 31855 boards on ebay, they're defective... I got some multichannel Max31856 boards on Ebay from the US that work well.. (I think it's Whizoo.com Edit: doesn't have a link to his ebay store) not cheap at $50 for a 4 channel, but not bad either. the cheap ebay thermocouples seem to work alright though.

There are some finicky differences between the Mega and Uno that make it so you can't just drop in the Lil'bb shield onto it, you need a board in between to shuffle some pins around.. Hakcenter should be able to tell you how many analog inputs are available, I think you should have enough to do what you need..

I was planning to put both sensors directly on top of the engine, but thanks for the heads up about the vibration. I think I’ll mount them to the firewall and run a length of tube to both instead. There is another supplier I see that says they are US made sensors, so I may try those.

I was looking at the Adafruit amplifier, I think they just want $15 or so. I’d like to use the Uno for ease of use with the CAN shield, but if the Mega is needed for more program memory and inputs, I can figure out how to make that work too. Would it be useful to have a prototyping shield dropped in too?

I was thinking that rather than having one box that does everything, having a couple in convenient locations, each with their specific duties, and they talk over CAN bus to each other.. Much less ratsnest.. you don't believe how many wires I have coming into that Mega, total cluster$#%k! And the Mega doesn't really have a whole lot of processing power either to do displays (which hold up other, more important things)...

^^ was what I was thinking. No need to make 1 thing do everything. It'll jumble up the code etc.

If you're mostly looking for just data, and not to use it as a reference 3d map table, I would just off load all the extra thermos and boost / back pressures to a separate unit, which you'll probably want to send to a LCD screen anyways.

AMP2 Corinthians 8:21For we take thought beforehand and aim to be honest and absolutely above suspicion, not only in the sight of the Lord but also in the sight of men.

First use would just be for gauge display, to start. I was thinking about using boost pressure or EGT monitoring more as a fail-safe. If boost pressure or EGT goes above a certain value, increase the vein position a little every second (or whatever time interval) until the value starts dropping, then decay the added position value after back under the threshold.

Edit: So I’m thinking I’ll use an Arduino Uno w/ CAN shield as the master, and an Arduino Mini to drive the LCD. The Uno will take in all sensor inputs and drive the VGT actuator, and push data to the Mini for display on the LCD? Use serial or SPI for comm between the controllers?

My thought was to keep the LCD and slave module light weight and compact so I could find/build an enclosure for it. I envision mounting it to the A pillar or Dash like an Edge Insight. I guess there are small can modules, like the MP2515 that wouldn’t add much bulk to it, and I would gain CAN bus transmission speeds.